For the past several days I've been having nothing but trouble with Kerio Outlook Connector. I have uninstalled and reinstalled KOC several times. Everytime I try to launch MS Outlook I get a message that a upgrade is downloading only to be followed by a "Can't open your default email folder, Outlook is closing". I will let the so called upgrade run it's course and at the end I get the following message. Update Process finished with Error 28403. Needless to say this situation is extremely frustrating and has caused me to lose one of my personal data folders in Outlook. Can someone help or do I need to uninstall Kerio Outlook Connector permanently?

This is because you're installing Kerio Outlook Connector version, which is different from your Kerio Connect server version. Download the Kerio Outlook Connector installation package from the Integrations web page on Kerio Connect. It will provide the correct version.

I went through the process you explained and got the same result. I went to the Integration with Windows button and clicked on "Download Kerio Outlook Connector". I downloaded the correct version based on your instructions, tried to launch Outlook after attempting to install the updated Kerio Outlook Connector and the same issue happens. Now what?

Is the downloaded version different from the one you installed previously? If so, is it higher or lower?
I think you need to uninstall Kerio Outlook Connector first and then install the package downloaded from the Integration page on your server.

The version I just downloaded is kerio-connect-koff-8.2.4-2559-p1-win.exe. The version that's loaded is kerio-connect-koff-8.2.2550.exe. When I try to open Outlook the upgrade window opens and then it tells me outlook won't open. Go all the way through the process again...and the upload process finished with error 28403 pops up again.

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